I just found an issue where I am trying to use the Facebox (overlay) plugin and dynamically build the link to get the overlay. everything works fine:
<a href="#listing-overlay{$ID}" rel="facebox">$Name</a>
except the pound sign '#' in the href is being replaced with the entire URL. Does SilverStripe do some kind of replacement behind the scenes with the pound sign...like a reserved word...and I am not aware?
the link ends up like this: http://4wayinvestments.tsg.net/listings/SearchForm?PropertyType[Office]=Office#listing-overlay9
when it should be like this: http://4wayinvestments.tsg.net/#listing-overlay9